Longitudinal edge drains have been used in kentucky for approximately two decades. Most were installed on the interstate and parkwaysystems. Currently there are hundreds of lane-miles in place. The first edge drains consisted of 4-in., Perforated, polyethylene pipe installed in a 12-in.-Wide trench. Various types of backfill were used. Some trenches were fabric wrapped and backfilled with crushed limestone aggregate of uniform size (approximately 3/4 in.). Other trenches were not wrapped and were backfilled with a natural sand. In these cases, the pipe was covered with a fabric sock. This paper dealsmostly with geocomposite (panel) edge drains, because most of the research and performance monitoring in kentucky in the past 6 years has been on that type of drain. Much attention should be given to details during installation and construction of the panel drains. Many problems encountered were the result of improper construction practices. Problems included compression of the inner core of the panel drain during compaction of the backfill, damage to flexible outlet pipes during construction, and improper drainage at the outlet. Outlet pipes should be installed at the proper grade. This helps maintain the velocity of the water in the drains, which helps to flush out silt and clay-size particles that enter the drain. The drains and outlet pipes should be well protected during the remainder of construction. Headwall distances should be designed on a project-by-project basis. This prevents exceeding the capacity of the drains. Breaking andseating the rigid concrete slab produces unstable situations in which silt-size particles are set in motion by cyclic loading and by the flow of water. If this silt source is sufficiently great, cloggingmay occur. Geocomposite fin drains are good alternatives to pipe edge drains because of their ease of construction, narrow trench widths, and more rapid response times. Care should be exercised in the design and construction of the drains to ensure that they perform properly. The core should be inspected after installation to ensure thatthe integrity of the core has been maintained throughout construction. This paper appears in transportation research record no. 1329, Geocomposite pavement drain systems 1991
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